Welding machine



Sept. 24, 1935. D. K. HOPKINS WELDING MACHINE Filed Dec. e, 1935 4Sheets-Sheet 1 full. .11..A

Sept. 24, 1935. D. K. HoPKlNs WELDING MACHINE Filed Dec. 6, 1933 4Sheets-Sheet 2 IN'SZ'ENCIP.-

l W I AT1-YE 4 Sheets-Sheet 3 INVERTER- D. K. HOPKINS WELDING MACHINEFiled Deo.

Sept. 24, 1935.

D. K. HOPKINS WELDING MACHINE Sept. 24, 1935.

Filed Dec. 6, 1953 4 Sheets-Sheet 4 INYEN-r DE.-

ulllllll." :|IIIIIII: ...llllllllllll .IIIIIIIII... ..."IIIIIIIIQ.

`Patented Sept. 24, 1935 UNITED sTATEs PATENT OFFICE WELDING MACHINEDurward K. Hopkins, Peoria, Ill., assignor to Micro Products Company,Peoria, Ill.

This invention relates to welding machines, more particularly to amachine for automatically butt-welding wire, rods and the like. y

One object of the invention is to provide a welding machine adapted togrip and feed automatically the ends of rods to be welded in such amanner as to form a satisfactory butt-welded joint therebetween.

Another object is to provide means associated lo with the gripping `andfeeding mechanism for timing the movements of the rods as the weld isbeing formed in such a manner that either a flash or pressure Weld iseffected.

A further object is to provide means whereby l5 rods or wires ofdifferent sizes and sectional proportions or the same made fromdifferent metals may be welded on one machine with uniformlysatisfactory results.

An additional object is to provide means whereby, when necessary, themetal adjacent the weld may be annealed or normalized subsequent to thewelding operation.'

Other objects will appear in the accompanying description and drawings,in which- Fig. 1 is a broken front elevational View of the device;

Fig. 2 is a broken side elevational view of the same;

Fig. 3 is a fragmented side elevational View of operating mechanism tobe described, taken from line 3-3 in Fig. 1; v

Fig. 4 is a fragmented sectional elevational view of operating andcontrol mechanism to be described, taken from line 4-4 in Fig. 3;

Fig. 5 is an enlarged front elevational view of the operating headportion of my machine similar to that disclosed in Fig. 1, showing partsin operated position, as will be described;

Fig. 6 is a view similar to that shown in Fig. 5,

with parts in another operated position to be described; K

Fig. 'l' is a perspectiveyiew of a gripping shoe used in connection withthe apparatus, as will be described;

Figs. 8 and 9 are perspective views of anvil portions cooperative withthe shoe shown in Fig. 7;

Fig. 10 is an enlarged side elevational View of the operating headportion of the device showing details oi' mechanism to be described;

Figli is a view similar to Fig. 10, taken from the opposite side andhaving certain portions broken away to permit clearer view of underlyingparts;

Fig. l2 is an enlarged sectional detail view of a control means to bedescribed, taken from line IZ-I2 in Fig. 6;

Fig. 13 is an enlarged detail sectional view of insulated bearingconstruction to be described, taken from line Iii-I3 in Fig. 6;

Fig. 14 is a fragmented detail sectional view of parts to be described,taken from line I4-I4 in Fig.v 10;

Fig. l5 is a fragmented sectional detail view of mechanism to bedescribed, taken from line |5I 5 in Fig. 11; 5

Fig. 16 is a fragmented sectional detail view of mechanism tobedescribed, taken from line Iii-I 6 in Fig. 10;

Fig. 1,7' is a fragmented sectional detail view 0f control mechanism tobe described; 10 Fig. 18 is a fragmented detail sectional view of aportion of the control mechanism, taken from line I8-I8 in Fig. 17; and

Fig. 19 is a detail sectional view taken from line Ill- I9 in Fig. 18.15

Fig. l of the drawings discloses my welding machine as generallycomprising an operating mechanism supported by a base member I0 uponwhich is supported a column member I I. Castors such as I2 may beattached, if desired, to enhance port- 20 ability.

Figs. 5, 6 and ll best indicate that the head mechanism includes duallevers I3 and I4, lever i3 being pivoted at I5 upon a lever I6, Fig. 1l,by means of an integrally formed trunnion Il ro- 25 tatably mounted inlever I6 and retained in longitudinal position therein by means of ascrew I8.

Lever I6 is pivotally supported, as best shown in Fig. 1l, by means ofcentering studs I8 and I9. Stud I8' is xedly secured in the frame 30structure 20, while stud I9 is adjustably mounted therein as shown.Complemental recesses in a shaft 2l co-operate with the studs to providean accurately centered bearing for the lever. The lever is insulatedfrom the frame and bearing 35 structure by means of a bushing 22.

Lever I4 is pivoted at 23 in the stationary frame structure, by means ofa trunnon portion similar to trunnion I1.

Secured to the inner side of the upper ends of 40 levers I3 and I4 arebearing blocks 24. In the lower faces of the blocks arcuate recesses areformed, adapted to movably receive beaded portions 25 of upwardlyextending rib portions of shoe members 26. The shoes are shown in per-45 spective in Fig. '7.

Disposed below shoes 25 are anvil blocks 2l and 28. Block 28 is xedlysupported by a bracket portion 29 integral with the frame structure 20,while anvil 2l is supported by a similar bracket 50 integral with leverI6.

To the lower ends of levers i3 and I4 are connected arcuate springmembers 29', the outer ends of which are pivotally connected to thelevers by means of screws 30. The springs are insulated 55 from thescrews and levers by means of washers 3l and bushings 32 as shown indetail in Fig. 13.

Outward flexing movement of the springs is limited by retaining bolts29".

The inner ends of the springs arepivotally se- 50 cured to a head member33 by means of screws 34. Head 33 is securedy to a depending rod 35 bymeans of a screw 36. Rod is pivotally connected at its lower end to afoot lever 31 by means of a removable pin 38, as shown in. Figs. 1 and2. A series of holes in the lower end of the rod provides adjustment ofthe foot lever in relation to the rod.

Reference to Figs. 2 and 3 will indicate that foot lever 31 is pivotedat 39 upon a bracket por tion secured to the column I I, also that aspring 4I is adapted to urge the foot lever toward an elevated position.

Reference to Figs. l and 5 will indicate that upward movement of thelever will operate through springs 29 to move the lower lever endstoward each other to rotate the levers upon the trunnion centers I5 and23 to move shoes 25 away from anvils 21 and 28.

Fig. 6 indicates that downward movementJ of the foot lever will bringabout spreading movement of the levers which results in placing shoe 25of lever I4 in contact with anvil 28 and the shoe of lever I 3 incontact with anvil 21.

It will be noted that levers I3 and I4 carry small abutment portions I3and-I4' which, when the levers are in position shown in Fig. 5, abut theanvil supporting brackets and that with lever I3 in the Fig. 5 position,any further inward movement of the lever will result in unitary movementof lever I6 upon its centers I8 and I9, this movement obviously bringingabout movement of anvil 21 away from anvil 28 to place the anvils in therelative position of Fig. 5.

Downward movement of the foot lever will result in spreading movement oflevers I3 and I4 to bring about abutment between the shoes and anvils sonoted, by means of which further movement oi lever I4 will be prevented,whereas in the case'of lever I3, abutment of shoe 25 against anvil 21will bring about a locked condition between levers I3 and I6, wherebyfurther movement of lever I3 will result in unitary movement of lever I6to move the anvils toward each other into position indicated in Fig. 6.

Springs 29 obviously form differential resilient connection between thelevers and are therefore adapted to provide equalized pressure of shoes25 against associated anvils or upon articles placed between them,regardless of non-uniform size of such articles.

Lever I6 is normally urged to open position by a spring 42, Fig. 14,operating an abutment pin 43 slidably mounted in a recess formed inframe 20, and inward movement ci' lever I6 is limited by the inner endof a shank portion of pin 43 abutting the bottom of the recess.

Outward movement of lever I6 is limited by an adjustment screw 43",Figs. 15 and 16, mounted in the frame structure 20 and carrying aninsulating button 43 and a knob 44 having an indexed flange 45. A stoppin 46 limits rotating move* ment of the knob and screw the describedassembly providing means for adjustably hunting operating stroke oflever I6in a predetermined manner.

Figs. 5 and 15 indicate that lever IS carries an extending arm 46 to theouter end of which is secured an insulating button 41, the latteradapted to rest upon a cap member 48 whichfis, in turn, supported uponthe upper end of a plunger member 43 o1' a dash pot mechanism shown indetail in Fig. 17.

The dash pot mechanism comprises a body member 50 provided with adownwardly extending `lever I6 is connected with a source of cnr'aclaren stud portion 5i by means of which. the body is secured to abracket portion 52 of the freine 2u.

Plunger 49 is provided with a plurality of ring portions 53, 53 and 54,whereby the plunger is slidably ,supported within a cylinder formed inthe body, rings 53 and 53' acting as guides while ring 54 is adapted toact as piston head to control movement oi 'the plunger. The cylinder andassociated ducts are normally .dlled with liquid.

Leading lirom the cylinder is a plurality oi horizontal ducts lili, thelower oi which communicates between the .loweiportion of the cylinderand a vertical duct titi having a needle valve mein ber 51 disposedtherein adapted to control the new of liquid therethrough.

The needle valve is made adjustable by means of its screwed mounting inbody 5il and is provided at its outer end with an .indexed knob 5B,whereby it may be adjusted in a predetermined manner.

The upper ducts 55 communicate between 'the cylinder and an enlargedupper portion of the vertical duct 56.

Reference to Figs. 18 and 19 will disclose that ring 54 is provided withapertures 59 and that a check valve disk 6D is retained against theunder side of the lower ring by a spring SI supported by a fixed Washer62.

Fig. 18 also illustrates a pin 63 slidably mounted within plunger 49 andabutted by a spring 64. By means of pin 63 abutting the bottom of thecylinder, the plunger 49 s constantly urged upwardly to 'follow anyupward movement of lever extension 46. Relatively quick upward movementof plunger 49 is permitted by reason of the liquid flowing throughapertures 59 past check valve disk 6U to the lower portion of thecylinder, whereas downward movement is retarded, in an adjustablemanner, by reason of the checking action oi disk S0 whereby any liquidflowing past ring 54 must do so through the ducts 55 and 56 with needlevalve 51 restricting the flow.

It will be noted that the lower portion of the cylinder is enlarged tosuch an extent that when piston ring 54 reaches a certain point, in itsdownward travel, the ring enters the enlarged portion of the cylinderwhereby the liquid may pass freely around the ring. This action willrender the needle valve no longer effective to retard downward movementof the plunger and the plunger will be free to respond, in a relativelyquick manner, to the pressure of arm 48 as brought about by thedescribed forced movement of lever I 5.

The foregoing will make clear that clockwise movement of lever I 6 maybe adjustably regulated by means of the dashpot. With this in mind, itwill be clear that, with parts in the position shown in Fig. 5, the footlever 31 may be pushed down, whereupon springs 29' will exert pressureupon levers I3 and I4 to bring about first, gripping con tact betweenshoes 25 and anvils 21 and lili, and second, an automatically. timedmovement of anvil 21 toward anvil 28, progressing for a iubrtaindistance at relatively slow speed followed by quick finishing movementto complete the stroke, this movement being adjustable as to extent andspeed by the means described.

It will be noted that levers I3 and i3 are in sulated from vtheremaining mechanism and that ont by means of a flexible coupling 65. Theopposite side of the circuit is connected with the frame structure 20,through a connector 66, ai; best shown in Fig. 16.

The transformen devices from which current is supplied are preferablydisposed within the column I I. Since they may be of any form ormanufacture, they will not be here described further than to say thatthey are suitably connected with levers I3 and I4 by which means theshoes and associated anvils become in fact electrodes and that thecurrent supply thereto is controlled by means of switch mechanismsassociated with my welder, as follows: y

Fig. 15 will indicate that a screw 6l is carrie in the upper part orlever it, the head of which abuts an opposing head oi a pin 88. Pin 68is made from insulating material and is slidably mounted in structureill. Fig. l2 illustrates that Athe pin extends into a chamber formed inthe frame structure in which is disposed a switch n mechanismAcomprising contact members and lil. Pin il@ passes throwgh contact duand abuts contact lil in such a manner that when lever t6 progressestoward center a predetermined distance, contact 'lil is removed fromcontact GQ to brealr the electrical circuit, whereas when the ioot lever3l is pressed down to move lever l@ bachl wardly, as described, thecircuit is automatically reestabiished.

A further circuit control means is provided in a switch mechanismdisposed adjacent toot lever 3l.

Figs. 2, 3 and l illustrate that this latter rnechanism comprises alever member lli pivoted upon column il at l? and urged upwardly at itsouter end by a spring 'd'3 supported by the base lil.

'Disposed below lever 'l i, enclosed in a suitable cover, is a switchmechanism comprising a con tact ld, a rio-operative contact spring l5and an actuating pin l@ composed or insulating material. lt will beapparent that lever "il, upon downward movement, is adapted to engagepin l@ to establish contact between members ifi and lil and upon upwardmovement to break the contact, which posttion is indicated in Fig. l.

Fig. l indicates that lever lll is disposed at right angles with footlever 3l, which latter carries a screw 'il adapted to engage lever llwhen the foot lever is moved downwardly, which movement oi the footlever results in corresponding movement of lever il to close the circuitbetween contacts it and lll, while upward movement thereof re suits inopening of the circuit.

lt is to be noted, Fig. 3, that lever il is so dis- Y posed as to beavailable for operation to close the switch independently oi lever 3l.The utility oi this will be explained shortly.

Figs. 5, 6, l0 and il illustrate that lever i6 and frame 2u haveupwardly extending portions which carry electrode clips comprising clipsprings 18 and reinforcing springs 1S. The utility of these will beexplained.

Secured to column ll is an upwardly extending bracket member Bil whichcarries a lamp and guard member el, whereby the operating points of themechanism may be properly illuminated without danger to the lamp, and avise mechanism comprising a stationary lower jaw 82 and a movable upperjaw 83.

Jaw 83 is movably mounted upon jaw 82 by means oi a screw 88 and isoperated by means of a hand lever 85, the same being rotatably mountedin upwardly extending portions 86 integral with jaw 82 and passingthrough openings in jaw a3 An eccentric member secured to the shank ofthe hand lever between extensions 86 co-operates with an extendingportion B1 of jaw 83 in such a of the dashpot or other timing means.

manner that manipulation of the handle results (in opening and closingmovement of the jaws.

controls for lever I6 are first adjusted to give the 5 desired extent ofmovement and the dash pot mechanism is adjusted to provide suitablespeed of operation.

The adjustments having been suitably arranged, the rods to be Welded areplaced upon 10 the anvils 2l and 2B respectively with their ends spacedin a predetermined relation, whereupon the foot lever 3l is fullydepressed, thus instantly clamping or gripping the rods upon the anvils,closing switch llt-'idw supply current to the i5 transformer, andbeginning a substantially slow progressive movement or anvil il towardanvil as controlled by the dashpot. Upon contact or the rod ends, thewelding process will begin and continued movement of the rod in anvil 2ltoward 2u that in anvil 2li will result in continued burning away of therod ends until lever l@ progresses sufiiciently to bring the screw (ilinto Contact with pin to brealr the circuit of switch @Q -lli. itsubstantially this point piston ring Sli enters the 25 enlarged portionof the cylinder to relieve the bach pressure provided by the dashpot andthus allow lever lf3 to duiclrly move short distance iorce the rod endstogether to effect a weld, of the i'lnal movement being limited by meansoi lo lever l@ engaging pin 33.

lt is apparent that by means of the several conx1 trol elementsdescribed, the mechanism be adiusted to perform automatically a cycleci? cperation which will produce a welded. joint between 35 s rodsplaced therein substantially as icllows'.'

The spaced rod ends are iirst moved toward each other to a point whereelectrical contact taires place, whereupon that portion ci the meta-l incontact is quickly burned away and an are is 4@ established whereby themetals are burned away as movement of the rod ends progresses at a relatively slow rate, which rate would ordinarily be such that removal ofmetal by burning progresses slightly laster than the rate at which therod 4,5 ends move toward each other. By this action, the original arc ismaintained during progress or the movement to a point where the currentis shut od, at which point the highly heated rod ends are suddenlyforced together under suitable pressure 5o to weld and upset the metal,whereupon at a'suit able point, further movement is prevented. Thedescribed preliminary burning action is edective to prepare the rodends, both as to temperature and conformity, for the final weldingaction.

The circuit of switch SQ-llt is rie-established immediately uponbeginning oi return movement of lever i6; however, the circuitas a wholere mains broken by reason ci simultaneous opening of switch M -'l5 asbrought about by release and so position, seeliig. 5. 35

For pressure welding operation, the operating cycle is substantially thesame, with the several adjustments described suitably arranged.

It might be stated at' this time that my de5 vice will perform its fulloperation as a welding 7@ machine of the resistance type Without the useIn other words, resistance welding of a certain class .of materials maybe readily accomplished by using the present machine in its normaloperation with 75 the exception that the dashpot or timing mechanism mayeither be adjusted for non-use or entirely removed.

For rods of circular or substantially uniform cross-section, anvilshaving recesses similar to those shown in Fig. 8 are used. For rods ofother cross-sections anvils of suitable form may be used, an examplebeing shown in Fig. 9 which shows an anvil adapted for use with rodshaving fiat or oblong cross section. Obviously, anvils of various formsmay be made interchangeable and are easily attached and removed by meansof screws such as 21' shown in Fig. 11.

As is well known, temperatures set up during a welding operation arelikely to bring about, in certain materials, undesired molecular changessuch as brittleness. To provide for annealing the area adjacent thewelded joint, the electrode clips 'I8 are available.

As has already been noted, lever I6 and frame structure 2U form oppositepoles of the secondary transformer circuit. It will be apparenttherefore that after the welding operation is completed, the rod may beremoved from the gripping devices and placed under the clips to form acircuit therebetween. With the rod in this position, the lever 7| may bedepressed by the operators foot to operate switch 'I4- 15 to supplycurrent to the clips, whereby the rod may be heated to any desiredannealing temperature, this being accomplished without operation of themechanism.

The vise 82-83 may be used -for temporarily holding the rods whilecooling or while burr is being removed from the Welded portions.

What I claim is:

1. A welding machine having in combination dual gripping mechanismselectrically insulated from each other and movable relative to eachother, means for supplying electric current thereto, the grippingmechanisms adapted to grip materials in spaced relation and to be movedto bring said materials into physical contact, manually operabledifferential means for gripping the materials in an equalized manner,means abutted by one of said gripping mechanisms for moving the samerelative to the other and adjustable automatic means for controlling theextent and speed of said movement.

2. A welding machine having in combination dual levers disposed in aparallel manner, one being pivotally mounted upon a stationary supportand having a movably mounted shoe member attached at its upper end, ananvil-electrode member supported upon said stationary support sodisposed relative to said lever and shoe as to be abutted by the latterwhen the lever is rotated upon its pivot in such a manner that materialsto be welded may be gripped therebetween, the other lever beingpivctally mounted upon a third lever and having a movably mounted shoemember attached to its upper end, an anvil-electrode member supportedupon the third lever so disposed relative to the second lever and shoeas to be abutted by the latter at the beginning of rotation of thesecond lever upon its pivot in such a manner that materials to be weldedmay be gripped therebetween, and upon continuation of said rotation toimpartunitary rotation of the third lever upon its pivot, the latterbeing so disposed relative to the iirst and second named levers that theaforesaid rotation of the third lever brings about movement of the anviland shoe associated therewith toward the anvil and shoe associated withthe rst named lever, autoamara-4 matic means co-operative with the thirdlever 'for controlling the speed of movement thereof,

manually operable differential mechanism :for moving the irst and Secondlevers in such a manner that the gripping pressure of said shoes andanvils is equal and for imparting the described movement to the thirdlever the same comprising a foot lever, and a supporting stand for thedescribed mechanism.

3. A device of the class described having in combination a, mechanismfor gripping the ends of materials to be welded in adjacent spacedposition said mechanism comprising dual anvils movable with respect toeach other, dual levers pivotally mounted adjacent thereto the same`having portions adapted to bear upon said anvils when said levers arerotated upon their pivots whereby said ends of materials are grippedbetween said anvils and lever portions, means for rotating said leversto effect gripping as aforesaid comprising a resilient toggle mechanismconnecting portions of the levers and manual means for operating thetoggle mechanism.

4. A device oi the class described having in combination a mechanism forgripping the ends of materials to be welded in adjacent spaced positionsaid mechanism comprising dual anvils at least one of which is movablewith respect to the other, dual levers pivotally mounted adjacentthereto, each having portions adapted to bear upon one of said anvilswhen the levers are rotated upon their pivots whereby said ends o!materials are gripped between said anvils and lever portions, means formoving said movable anvil and its associated lever toward or away fromthe opposite anvil and lever comprising a support for the former movableby means of.

movement of the associated lever, and means for moving the levers toeiect gripping of the materials and movement of said mov-able anvilcomprising resilient toggle mechanism connecting portions of the leversand manual means for operating the toggle mechanism.

5. A welding machine having in combination dual gripping mechanismsmovable relative to each other whereby materials to be welded may begripped in spaced relation and subsequently moved toward each other,manually operable mechanism differentially connected with said grippingmechanisms whereby a single movement of said manually operable mechanismfirst causes actuation of the gripping mechanism to grip said materialswith equal pressure and finally movement of at least 'one of saidgripping mechanisms toward the other to bring said materials intoabutment i'or welding.

6. A welding machine having in combination dual gripping mechanismsmovable relative to each other whereby materials to be' welded may begripped in spaced apart position and subsequently moved toward eachother, manually operable mechanism diierentially connected with saidgripping mechanisms whereby a single movement of said manually operablemechanism first causes actuation of the gripping mechanism to grip saidmaterials with equal pressure and iinally movement of at least one ofsaid gripping mechanisms toward the other to place said materials inabutment for welding the assembly adapted to operate in such a mannerthat said grip pressure is automatically increased in accordance withthe pressure of abutment between the surfaces of the materials.

DURWARD K. HOPKINS.

